Male college swimmers (N = 26) were tested before and at weeks 4, 8, and 12 of a 12-week training program. Ss completed three pairs of 200 yd freestyle swims with one-minute rest intervals at self-perceived effort levels of 75%, 85%, and 95% of maximum. A variety of physiological measures were obtained. Swimming velocity at 4 mmol of blood lactate (V4) was calculated for each testing session.

V4 changed significantly by week 8. Stroking efficiency and stroke rate also improved significantly by week 8. There was no change in stroke length or breakout distance across the period of study. V4 was highly related to stroking efficiency, stroke length, and breakout distance in a multiple correlation (R = .87).

Implication. Collegiate male swimmers improved in technical efficiency and physiological factors across 12 weeks of training. After 8 weeks, most parameters had achieved the maximum amount of change.